Cutting-torch



, M. K. DUNHAM.

.CUTTIN6`TORCH. APPLICATION FILED IAR; 4, 1919".-

INVENTOR ATTORNEY UNITED sTATEs PATENT oEEIcE.

MELBOURNE KEITH EUNHAM, or cHIcAeo, ILLINoIs.

CUTTING-TORCH.

. Specification of Letters Yatent.

Patented May 6, 1919.

Application med .Maren 4, 1919. serial Nq. 280,52?.

To all whom it may concer/n.: l

Be it known that I, MELBOURNE KEITH DUNHAM, a citizen of the United States, and a resident of Chicago, in the county of Cook and State of Illinois, have Iinvented certain new -and useful Improvements in Cutting-Torches, of which the following is a s pecication.

This invention is an improved cuttingtorchy ofthat general type which is adapte to apply a jet of heating flame to the material to be cut, to heat said material to the necessary or desired high temperature, and

to deliver oxygen or a gaseous-oxidizing` mixture to the heated material to oxidize it and remove the oxid to produce a cut, as is well understood by those skilled in the art. In common practice, the heating iame, which may be a mixture of oxygen and acetylene, or hydrogen, is applied before the oxidizing jet and means are provided for quickly opening and closing the supply to the oxidizing jet at the beginning and end of the cutting operation. Such means commonly `includes a valve. openable against a spring by means of a valve lever so positioned in respect to the handle of the torch that it may be easily operated by the thumb or fingers of the hand which grasps the handle and carries the torch. A

The novel features of my invention reside primarily inthe means employed for operating and controlling the cutting oxygen-- .valve. The main object of my invention is to provide a simple, easily operated and inexpensive construction in which a compar: tively stron spring may be used to no mally hold t e valve to its seat but in which vthe valve may be easily opened against the action of the spring, and may be` automatically locked inl open position 'or easily \re' leased to permit closing. In my improved construction, -I provide a valve operating lever pivotally mounted at or adjacent to one end of the handle and co-acting with the Y valve stem at ashort distance from the pivotal point. The swinging end of the lever preferably terminates ad]acent to-the 'opposite end of the handle and, in swinging, slides along a pivoted locking member extendin substantially at right angles to the genera direction of the handle.l The lock-- ing member is so designed that its normal engagement with the valve lever will prevent the return movement of the latter to closed valve position but the locking member is conveniently positioned and easily operated to release the valve lever at Will. This locking device serves merely to relieve such strain on the hand of the operator as mightiresult, were it necessary for him to hold the valve lever in depressed position against the action of the spring While conducting a cutting operation for a considerable length of time. y

I preferably form the handle or grip member of a piece'of tubing encircling the oxygen and acetylene or other gas conduits leading to the head.A This tubing at its opposite ends engages with separate metal blocks or collars encircling or. securedto the conduits and as an important feature of my invention I form'these blocks or collars with lugs or other pivotal connections for the valve lever and the lever locking vmember so -that iirm and rigid supports are provided for these pivoted members beyond the ends of the tube and Without engagement with or connection torthe thin wall of the latter. This also permits the valve lever to be locked at va point a considerable distance from the fulcrum and valve stem `where the strainon the parts is therefore comparatively small.

In the accompanying drawing I have 'illustrated one of many possible embodiments of my invention and 1n connection which acetylene and oxygen conduits may .be connected. Atl the opposite side of the block is a transverse lian'ge 13, into which' three separate conduits 14, 15, and 16 may be rigidly secured. The block has a passagetherethrough connecting the conduit 16 with the boss 11, whereby the acetylene may befdelivered to said conduit. The iiow of' the acetylene may be controlled by a needle' valve 17 or other controlling means.. The boss 12 has a'passage 18leading to the central conduit 15, the flow through this con- "duit being controlled by a needle valve 19 or other controllingmeans. The boss 12 also scale, portions thereof aev . has a passage 20 leading to a valve chamber 21 and from which the oxygen may flow to the conduit 14C when the valve 22 is opened against the action of the spring. The valve 22 has a stem 23 extending through a suitable packing to the exterior of the block and y into operating relationship with the valve spring.

The handle of the torch is formed of a piece of tubing 26 encircling the rear portions of the conduits and spaced therefrom. As shown, the rear end of this tubular handle member telescopes on to a cylindrical portion 27 of the block 10 and it may be secured to the latter by screws 28, or in any other suitable manner. At the opposite end of the tubular handle 26, there is employed a second block or collar 29 having separate openings therethrough for the three conduits 1-1, 15, and 16 and also having a reduced portion telescoping into'the end of the tube 26. The tube is thus held rigid in respect to the conduits but spaced therefrom.

The valve lever 24 lies adjacent to but normally spaced slightly from this tubular handle and terminates adjacent to the forward end of the latter. The collar or block 29 is provided with a lug 30, to Which is pivoted a locking member 31. This is shown as extending through an aperture 32 in the valve lever and as being provided With a recess 33 in one side thereof, which may receive a portion of the valve lever at one end of the aperture 32. A spring 34 normally presses the locking member 31 in such a direction as to hold it with the recessed or notched side against the valve lever so that as the valve lever is depressed orsqueezed toward the handle, it will slide down the side of the locking member until it comes opposite the recess 33 and the locking member will then be swung into operative or retaining position. Although I have shown the locking member with only a single recess in the sidethereof, it Will of course be evident that a larger number of recesses or notches may be provided, if it is desired to hold the valve open to other than one predetermined extent. Merely to prevent the free end of the valve lever from swinging away from the handle to an undersired extent when the oxygen valve is closed, the

locking member 31 may be provided with a head 31 which cannot pass through the recess 32 but which may be unscrewed and removed in case it is desired to swing the lever 21 outwardly beyond the normal closed valve position.

I have shown the three conduits 14, 15, and 16 leading to a head 35 to which a tip 36 is detachably secured by-a union nut 37. I have not shown the various passages through the head and tip or through the block 10 as the particular arrangement of said passages forms no portion of my present invention and may be in accordance with any design preferred by the manufacturer.

It will be understood that the oxygen and acetylene iiowing through the conduits 15 and 16 mixes in the head to form the heating flame mixture, while the oxygen supplied through the conduit 14 may be controlled by the valve lever when it is desired to begin or end the cutting operation. This oxygen ordinarily is delivered through a separate passage in the tip from that in Which 'the heating mixture flows.

Having thus described my invention What l I claim as new anddesire to secure by Letters Patent is:

1. A cutting torch having a plurality of gas conduits, a tubular handle encircling said conduits, separate members at each end of said tubular member for spacing the latter from said conduits and holding it rigid in respect to them, a valve for controlling the How through one of said conduits, a valve lever pivoted to one of said members, and a locking or retaining element pivoted to the other'of said members and engaging with the free end of said valve lever.

2. A 'cutting torch having a tubular handle or grip member, a plurality of conduits extending therethrough, spacing members at each end of said tubular handle for holding it rigid in respect to said conduits, a valve for controlling the flow of gas through one of said conduits, a valve lever pivoted to one oit' said members and extending lengthwise of said handle and of greater length than said handle, and means carried by the other of said members and movable in the direction of the length of the handle for engaging with the free end of said lever to lock it in open valve position.

3. A cutting torch having a valve block, a head, a plurality of conduits connecting said block and head, a spring pressed valve within said block for controlling the How through one of Asaid conduits, a lever pivoted to said block and extending approximately parallel to said conduits toward said head, and a pivoted member extending approximately at right angles to the general direction of the length of said conduits adjacent to the free end of said valve lever for engaging with the latter to hold the valve lever in open valve position.

4. A cutting torch having a head, a plural'ity of substantially parallel gas conduits leading thereto, a spring pressed valve for controlling one of said conduits, a pivoted valve lever extending in the general direction of the length of said conduits and having its freev end movable toward saidconduits and provided With an aperture therethrough, and a retainer extending approximately at right angles to the general direction of said 10 lever through the aperture of the latter and having a recess for receiving and retaining the valve lever and holding 1t 1n open valve position upon the movement of the free endl of the lever toward said conduits to a predetermined position. 9

Signed at Chicago in the county of Cook and State of Ill. this 1st day of March A. D. 1919.

MELBOURNE I KEITH DUN HAM. 

